What is the least common multiple of 10 and 20? Another way to say this is: $\lcm(10, 20) = {?}$
Answer: The least common multiple is the smallest number that is a multiple of 10 and 20. We know that 10 x 20 (or 200) is a common multiple, but is it the least common multiple? Write out the multiples of 20 until we find a number divisible by 10. 20, So, 20 is the least common multiple of 10 and 20.